The builds distributed on this site are strictly test builds and are only to be used if you know what you're doing. These test builds are released whether they are buggy or not and will generally not be supported by the LS Dev Team or the Independent Litestep Team. If you're looking for supported dev builds that will normally be stable then you should wait until the .24.7 release or download an official IndieStep build. The official LS .24.6 documentation is now available as a separate download.
To install a new build from scratch, download the latest build, or a build of your choice from the archive. You will need a theme to actually use Litestep.
To upgrade a build, download a build dated after your current build.